Fumes
by the-spoon-of-doom
Summary: Optimus's reproductive protocols get in the way of Megatron trying to beat the scrap out of him, and it turns out to be a lot more difficult trying to fight a mech that wants to clang you, rather than a mech that wants to kill you. G1, Sticky, Dub Con.


Disclaimer: Not my characters, not my universe, not my anything.

Warnings: Loads. Sticky sex, Dub Con, a bit of canon violence, and there's a swear in here somewhere. I think.

Excuses: Too many to list.

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><p>"<em>Love is a smoke made with the fume of sighs<em>"

William Shakespeare, Romeo and Juliet

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><p>Since the dawn of civilisation young Cybertronians had been terrorised by insensitive medics and overprotective creators alike with grim tales of heat cycles and what they entailed. Horror stories of young adolescents caught out in public when their cycles hit was a common tale to hear. Of course Optimus had long since learned that the exaggerated rumours were far from the truth.<p>

Having been sparked and upgraded in Iacon itself Optimus was no stranger to the delusional outlooks high and mid caste bots tended to have on everything that had anything to do with interfacing. As a result heat cycles were not, and never had been, a socially acceptable subject to bring up with anyone but your own medic, hence ignorance spread.

Modern mechanical medicine made 'traumas' such as heat cycles a thing of the past though. There wasn't a mech to be found since the golden age that hadn't been fitted with baffles or at least some form of preventive tinkering.

But having now known and spoken to mechs who had suffered and survived through a full heat cycle, Optimus had come to realise that everything he'd known about his own cyberology had been a lie.

The only effect a heat cycle had on the Cybertronian going through it was increased fuel efficiently -resulting in the bot in question developing a unique but temporary scent- and subconscious EM field flaring. Far from the uncontrollable urges and wanton displays Optimus had grown up fearing.

However, what a heat cycle _did_ do was turn anyone within olfactory sniffing distance into a frisky, rutting hooligan of a mech who'd stop at nothing to satisfy what their base coding overruled their processor to tell them was a fellow Cybertronian in desperate need of a spiking.

Since Optimus had no desire to be clanged seven ways into the next stellar cycle by a base full of horny Autobots he, and everyone else for that matter, had their contraceptive upgrades checked on a regular basis.

"Your frame wants to go into a heat cycle," Ratchet informed Optimus during a routine checkup as he finished his scan. "I want to secure those baffles, just as a precaution."

Optimus nodded his consent. It was a fairly standard -though invasive- procedure, better than the alternative at least.

Ratchet worked quickly and efficiently and before Optimus had much of a chance to cringe, he was finished. "There," Ratchet patted his thigh as a sign that he could sit up again. "That should do it. Nothing short of a blast from Megatron's fusion cannon itself will loosen those up."

At the time Optimus had smiled, thanked Ratchet, and left, but with hindsight, it felt all too much like tempting fate.

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><p>Optimus barrelled through the dirt at full speed, bypassing the smoother human built roads to get to the power station the Decepticons were raiding sooner. He could see the rising smoke and chaotic swarm of disorganised seekers from here. His convoy of Autobots weren't far behind, but few of their alt modes could handle the rough terrain and were sticking to the tarmac.<p>

There was no time to wait for them. Megatron needed to be stopped before human life was put at risk. The Decepticons had the sadistic tendency to torment prisoners left at their mercy for too long. Their bloodthirsty nature and short attention spans often resulted in human massacres when left to their own devices.

Luckily the plant was nearby, and Optimus passed many escapees as he charged through the security gates the Decepticons had ripped open. There didn't seem to be any hostages, which would make things easier.

From what Optimus could hear Starscream and his seekers were too preoccupied shrieking at each other to act as efficient sentinels, and Megatron was given no warning when Optimus transformed and leapt through a blasted hole in the side of the power station.

"Megatron!" He shouted to announce his presence, taking some small satisfaction in how Megatron physically flinched at the sound of his voice, "Stand down!"

Unsurprisingly his enemy had no intention of doing anything of the sort. Megatron's face twisted into a snarl, his frame stance shifting from proud and victoriously arrogant to dangerous and feral as battle protocols fired into life.

"Prime!" Megatron spat, lifting the arm mounted with his fusion cannon. "Deactivate him!"

The Decepticons that had been sucking the plant's power cores dry dropped their cubes and unsubspaced weapons. Optimus dived behind a pillar as unaimed blaster shots flew past and scorched the walls behind him.

He heard Megatron's rasping bellow above the noise just before the whir of a fusion cannon. There was a flash of heat and bright light seared Optimus's optics.

"Come out and fight, coward!"

Optimus obliged, rolling out from behind the pillar and charging at Megatron, knowing he had less than a breem before the Decepticon's high powered weapon could fire again.

Megatron was ready for him, his pedes spread in a wide stance. He stumbled when Optimus hit him, but lost no ground, and Optimus quickly found himself winded when Megatron span for momentum and slammed his heavy pede into his abdomen, where the armour was weakest.

He backed away, intakes sucking in air desperately as he tried to straighten up. But Megatron was relentless in his fury and drove a fist into the side of his helm, knocking him off his equilibrium and sending him crashing to the floor.

He glimpsed a pede about to stamp down on his throat and rolled to the side just in time. The floor shook with the force of the missed blow. He pushed himself up, but before he had a chance to stand Megatron swung another kick at his abdominal plating. It was a low, dirty move, and Optimus hadn't expected it, even from Megatron. He fell back to the floor with a pained grunt and heard something loose rattle inside him.

The other Decepticons had left. From what Optimus could hear with his ringing audials they were outside trying to fight off the arriving Autobots. His mechs wouldn't break through in time to save him, but at least the Decepticon's plans had been foiled.

Frame aching on the floor, Optimus waited to receive the scorching heat of a fusion powered weapon and some sort of a cruel parting words from Megatron himself. But there was only still silence.

Grimacing, Optimus risked rolling into his back, exposing his more delicate and already battered front to the warlord.

Megatron was still standing over him, but the hate that twisted his expression had transmuted into something else, something Optimus struggled to comprehend. Was he glitching?

But then, slowly, Megatron's expression changed again, his confusion melting away into a scowl. Optimus felt his hot, sizzling energy crackling in the atmosphere, differing somehow to the usual violent aura the Decepticon gave out. He wasn't sure what was keeping him in place at Megatron's pedes, where he was at the warlord's mercy, but something, some unconscious part of him, wanted to stay within his reach.

Having never been one to listen to unreasonable instincts, Optimus cast those thoughts aside and forced himself to move, shoving himself upwards and back to get some distant between him and the pedes that had moments ago been attempting to crush his throat cabling.

The sudden movement broke whatever spell Megatron had been under and drove his enemy into action again. Optimus yanked a weapon out of subspace. It was kicked from his servo before he could aim and went skidding across the large open room, far out of reach.

He tried to scramble after it but Megatron stalked forwards, black servos reaching for him and wrapping around one of his legs, dragging him back. Optimus winced as his armour scraped across the polished floor, leaving blue and red paint scuffs in its wake.

"You may succeed in deactivating me Megatron," Optimus threw at the warlord, suspecting these may be his last words, "But the matrix will choose another mech, just as determined to extinguish your evil!"

He thought they'd been rather good, as far as last words went. A pity only Megatron was present to hear them.

"Shut up you fool!" Megatron barked, and to Optimus's immense surprise, dropped to his knees before him, servos still tightly clutching his leg, "Throwing yourself at me won't save you!"

Optimus had to restart his optics, sure the blow his processor had taken earlier in the fight was now playing tricks on him. Megatron's servo felt very warm against his armour, and though it was gripping hard, it didn't feel uncomfortable. Optimus fought back a squirm and tried to organise his thoughts. The fact that he hadn't pulled away hadn't even entered his mind.

"Stop it Prime," Megatron then hissed low, his denta gritted together as if he was under great duress.

Optimus would have gladly stopped whatever he was supposed to have been doing if only Megatron would start acting like his usual, violent, merciless self. Because this was just weird.

He shifted the leg caught in Megatron's grasp, and the servo on his armour tightened, "I'm-" he tore his optics away from where he was being touched somewhat inappropriately to refocus on Megatron's snarling face, "I -release me!" He suddenly found the sense to demand.

Megatron did no such thing, and another servo landed on his other leg. Optimus's tank leapt when he was yanked closer to the kneeling warlord and leant back as Megatron closed in, moving close enough that Optimus could see the rapid brightening and darkening of his red optics.

"You know what you're doing!" He snapped, and Optimus could feel the Decepticon's intakes working fast and heavy against his plating, could see Megatron's olfactory sensors noticeably testing the air.

Optimus tested it for himself. What could he possibly be-?

It clicked into place in his processor, and realisation and dawning understanding was marred with horror.

"No!" He threw out his servos, shoving at Megatron's broad chest plates to get him off, get him away, quickly. "No Megatron, stop!"

But Megatron wasn't budging. It had taken Optimus too long to realise what had happened. All that time he'd been feeling awkward on the floor Megatron's stud protocols had been busy at work overruling the warlord's processor, shutting down his normally dominant codes one by one.

Things like a millennia of hate and the burning desire to have Optimus's helm mounted above his throne were now gone from Megatron's mind. Now there was only one thing Megatron's stud protocols wanted the warlord to do, and that was fuck the heat out of the unfortunate mech beneath him.

But Optimus had always believed that the processor was more than a mere slave to base coding. "Megatron!" He tried to reach through to his enemy as large, warm servos slid up his legs, "Megatron, snap out of it!"

Megatron was far too busy to listen to what he had to say, clawing at his thighs, trying to spread them apart as Optimus struggled to keep them locked together. He could smell himself now, the tangy metallic scent wafting from beneath his armour that must have been a result of the heat cycle.

He could feel Megatron purring, a satisfied rumble that shuddered all through his frame and tickled at Optimus's armour where their plating met. Megatron's face came down to press against Optimus's shoulder, his intakes working deep as he appeared to savour the alluring scent. With a hum that Optimus felt on his derma plating the temperature started to rise rapidly, heat radiating off Megatron's frame as the Decepticon's systems readied itself for procreation.

Optimus abandoned his attempts at dislodging Megatron's heavy frame and grabbed his helm instead, straining to pull the warlord's face away from his shoulder. He slapped a servo over the lower half of Megatron's face, hoping to obstruct his ability to smell him and maybe just bring him back.

"Megatron listen!" He shouted in the grey mech's audials, "You're not yourself! You don't _want_ this!"

His attempts at reasoning with Megatron only distracted him though. Megatron managed to wretch his helm free of Optimus's restrictive servo and in the resulting struggle caught him off guard and wedged a knee between his thighs.

He was still himself enough to bark out a triumphant laugh at the small victory, so Optimus punched him square in the face.

Since negotiation didn't seem to be working he'd just have to resort to violence. Like he did with everything when Megatron was involved. Unfortunately his enemy was just as prepared to get a little rough in order to achieve his goals.

Thick digits crammed themselves into the gap between Optimus's armoured facemask and natural plating. Metal groaned and screeched, and Optimus felt a sharp sting as it pulled at the sides of his helm. There was a snap, and cool atmosphere washed across his lower face. The exposure somehow made him feel more vulnerable than Megatron's thigh between his legs.

Which was rather crudely rubbing against his intimate panels in ways which were too pleasant to be acceptable.

"Megatron!" He snarled, voice deepening with the strain of trying to extract himself from Megatron's grasping -but tempting- clutches, "Megatron- Don't -make me- hurt-uuhhm!?"

His exposed jaw was grasped and pulled into a rough and unexpected kiss, muffling his threats. He tried to turn his helm, but strong servos kept him in place. Megatron's slick glossa pressed against his sealed lip plates, licking and probing teasingly to try and gain the access Optimus was denying him.

It would have worked, had Megatron not tweaked a sensitive wire on his hip joint. He gasped, and Megatron moved swiftly, thick glossa delving deep and twinning around Optimus's, forcing him to taste his enemy's oral fluids. Optimus grimaced through it, forcing himself to not acknowledge that it was revoltingly... pleasant.

Though he hadn't been sure what to expect from a Decepticon when it came to smooching, the kiss was surprisingly denta-free. Unwanted, invasive, and dizzying, but thankfully painless.

He hadn't realised just how much he wasn't minding it until he caught himself reciprocating -tilting his helm for accessibility, flicking his glossa out to meet Megatron's- and rocking his frame back against the Decepticon. Dear Primus, he was encouraging him!

At least Megatron was acting under the influence of base coding. HE had no excuse whatsoever! This was bordering on treachery! Fraternising with the enemy!

He yanked his helm free, able to do so now that Megatron's servos weren't clamped around it, and tried to shake off the warm flush building in his frame. "No," he told Megatron breathlessly, "This- we shouldn't. You have to-"

It was difficult to speak with Megatron's hot mouth nipping at his throat cabling, difficult to think with one of his huge, powerful servos so very close to his tingling interface panels. His frame wanted to arch into the pressure, he wanted to just lay back and let Megatron's protocols take care of everything. It was only a heat cycle. No one would blame him. Right?

Megatron's groin was shoved right up against Optimus's aft plating, and he could _feel_ the pressure behind it, the burning heat beneath the Decepticon's panel that was a spike desperate to break free and bury itself deep in something warm and wet and probably him.

Optimus placed his servos on Megatron's shoulders and tried one last time, halfsparkedly pushing the large mech away, "No..."

Megatron was heavy and determined and didn't move an inch, and as thick digits pressed and fumbled around the edges of his valve panel, Optimus's servos went from pushing at his broad shoulders to clutching them like they were his last lifeline. With a quiet click that sounded like a thunderclap in a room silent save for intakes and cooling fans, Optimus's panel opened.

A deep, sickeningly satisfied engine rumble shuddered through Megatron's frame. Optimus grasped at enemy armour and struggled to stifle flinches as curious digits touched him, stroked him, pressed between dampening mesh folds and brushed sensors that sent his spark spinning.

A soft "_Prime_..." was breathed into his clavicle seams, and Optimus's intakes stalled because Megatron was himself enough to register who he was doing this with. His valve tightened and grew wetter at the thought, the callipers gripping at the lone digit Megatron was slipping inside him with such uncharacteristic care.

"Megatron..." He murmured back, thighs falling open as if it was perfectly acceptable for his sworn enemy to be knuckle deep in his valve.

Megatron was growing restless, mouthing and breathing and nuzzling at the cables of his throat, his huge frame in constant shifting motion above Optimus, pressing and rocking down onto him. Amongst the pinging of heated metal Optimus heard a sharp snick, and the erotically distinctive hiss of a spike pressurising.

He daren't look down.

Rough servos better suited for mining and war than foreplay and 'facing ran up Optimus's frame. Derma plates tingled and twitched in wake of the warlord's touch. Humid exhaust rushed across his bared face and his optics focused on Megatron again as the Decepticon's face pushed close, the blunt edge of his olfactory sensor brushing Optimus's cheek.

Red optics dimming with ferocious desire, Megatron hummed, the sound deep enough to vibrate straight through armour and protoform to Optimus's spark chamber. It was bizarrely arousing, sending the callipers of his valve into a throbbing, twitching frenzy.

He kept his composure as best he could, thigh armour twitching as a warm stiffness bumped the joint between his leg and groin. Megatron's hips shifted, and Optimus felt the Decepticon's field crackle and fizz with a buzz of energy as he lined himself up. The broad head of Megatron's spike met the outer folds of his valve, and through it Optimus could feel the powerful charge running up and down the length of the Decepticon's interface array.

Being no stranger to what a rough frag entailed Optimus prudently curled his arms around his enemy's thick neck, and held on.

Megatron pressed forward, gently at first, easing himself in, and Optimus's mouth dropped open in a silent moan as delicate mesh stretched to accommodate the Decepticon's substantial girth. It was good, so good, and Optimus had to bite his glossa to keep from saying so, his valve eagerly taking Megatron's broad, pulsing spike ridge by ridge as the warlord rocked gradually deeper.

But then the stud protocols must have overruled whatever little control Megatron had clawed back. With barely much more warning than stiffening shoulders, Megatron thrust forward swiftly, sinking his entire length into Optimus's softening valve with a rumbling growl.

Optimus tensed, "Easy!" He cried, servos shaking on Megatron's armoured back plating.

Megatron groaned thickly against the side of his helm, already drawing back. His spike glided smoothly along Optimus's somewhat abused callipers, and the sting somehow adding to the warm pleasure that had began to build below his tank.

And then Megatron came back in, strong and deep, and fulfilling in ways Optimus could never have imagined. His gasp warbled into a moan, and the sound of his gratification accelerated Megatron's pace, the drag of his spike against Optimus's interior sensors built friction and charge quickly.

Optimus had never been in the nature of blaspheming, but he did then, and Primus's name was both gasped and muffled against Megatron's pauldron. The electric pulsing of Megatron's spike as he moved was too good -too intense- for Optimus to recall appropriately Primely conduct.

His spark spiralled and thrilled in a confusing disaster of despair and ecstasy. The irony that the only thing he had to cling to as he endured -_savoured_- this ordeal was his arch nemesis -a megalomanic warmonger with an unhealthy preoccupation for ending his life- was so cruel of fate that he could have laughed.

Except he was too busy moaning

The scent of Optimus's heat strengthened with arousal and was now converging with the foreign aromas coming off of Megatron. He breathed it in, searching for anything to anchor himself to reality, to not get lost in his own base coding. But Megatron was all warm oil and iron, and it was delicious.

Charge crackled and it was too much. Optimus dragged his servos across Megatron's back, his digits painting blue scars in the Decepticon's matt grey finish. His pedes left the floor to twine around Megatron's legs, to keep him close, to keep him deep.

His overload was building, tightening his joints and plates and valve, and he shook his helm, optics offlining as he tried to push it back. He couldn't enjoy this. Being an unfortunate victim to another mech's archaic protocols was one thing, but willingly submitting to the enemy-

A Prime was supposed to be more than just base coding and heat cycles!

But Megatron was seated deep within his frame and must have known what he was forcing back, what he was refusing to say. His intakes were heavy on Optimus's cheek and his thrusts slowed but deepened.

"No!" Optimus gasped, denta gnashing, thighs clenching with crushing strength around Megatron's hips.

The pressure surged, the charge sizzled, and overload burst forth, washing through his circuits in a warm wave of release. He seized it, rocking his hips back into Megatron's firm thrusts to draw out the throbbing ecstasy of the moment before it began to fade.

He was barely down from his high when a low purring groan tickled his audial and Megatron's heavy servos tightened on his waist and hip. Another wave of warmth washed through him, and he shuddered at the secondary charge and revoltingly liquid sensation of his enemy's overload.

And it was over.

The weight of the recovering warlord above him was suddenly no longer comforting, or even erotic, but crushingly claustrophobic. Megatron's sighing mouth on his audial was sickeningly damp, breathy, the panting of a well-satisfied mech. He felt the spike resting deep within his intimate array twitch, and begin to depressurise.

Optimus kept his servos splayed flat on Megatron's scapula plates, wary of what movement might bring, of disturbing the sated but _armed_ warlord pinning him to the floor with nothing but dead weight and sheer presence. Whose stud protocols may or may not still be in effect.

With a grunt, Megatron shifted, withdrawing from Optimus, leaving him empty and used. Lubricant tainted with Decepticon transfuild slithered out, tickling Optimus's plating as it dripped. Cringing, Optimus sent a command to reseal his valve, wishing he could do the same with the facemask Megatron had ruined and flung across the room.

A dim red glow was cast over the arch of Optimus's cheek as slowly, Megatron turned his helm, lifting it out of the nook between Optimus's throat cables and shoulder plating to peer lazily at his face. Optimus met his gaze, half aware that his intakes had stopped cycling air, and slowly, as the Decepticon's memory cores re-connected with conscious processors, Megatron's optics brightened, his frame tensed, armour plates locking together tight.

Optimus couldn't trust himself to speak, so Megatron did first.

"...Prime..." There was almost a question in his tone, a cautious edge to his voice.

Optimus's throat worked around words he didn't dare speak. He couldn't tear his optics from Megatron's face, held just inches from his, and felt heat grow under his facial plates at the intense discomfort of the situation. He was still slick from their fornication, Megatron's thick spike still a ghost sensation in his tingling valve.

With that last mortifying thought the proximity of his enemy grew too much for him. He tested Megatron's weight, and the warlord noticed, pushing off and scrambling to his pedes, bright red optics still staring down at Optimus sprawled on the power station floor.

Before either of them could speak a crash outside turned their helms, the blaster fire and explosions of their warring factions loud and close. Optimus's spark lifted, his Autobots had broken through enemy lines.

A war machine to his core, Megatron's battle protocols whirred back into life instantaneously. Weaponless, disorientated, and exhausted, Optimus flinched, knowing that though Megatron's optics weren't on him that fusion cannon soon would be.

And with this heat still cycling through his frame, in a matter of breems if he didn't have a smoking hole in his chassis he'd have a Decepticon between his legs instead.

He had to get away, from everyone, Autobot and Decepticon alike. With Megatron distracted, he moved, snatching up the weapon he'd lost in their pre-romp fight. He shot at Megatron as he fled, sure the Decepticon would follow if he wasn't incapacitated. There was a snarling roar of pain but Optimus didn't look back to see where his blast had hit.

He leapt into a transformation sequence, charged across the wide open floor of the power station, and out the cargo bay on the other side.


End file.
